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El Ninos are characterized by a shift of warm surface water from the western to eastern equatorial Pacific due to weakening of easterly trade winds. This shift is associated with the pycnocline (or thermocline), the large vertical density gradient beneath the surface mixed layer, shoaling in the west and deepening in the east, inducing a redistribution of ocean heat with global impacts. Here the response of the Equatorial Pacific Thermostad, a layer of low vertical stratification below the pycnocline to, El Nino is investigated using a monthly Argo float climatology and Argo float deep velocity data. A mean, seasonal cycle, trend, and time-lagged linear response to the Nino3.4 index are fit by least squares to temperature and salinity at each grid point as well as to deep float velocities (omitting the trend). The results of these fits are used to characterize the response of physical properties in the Thermostad, including layer thickness and velocity, to El Nino by comparing the mean properties following neutral conditions (Nino3.4=0 degrees C) versus those following a moderate El Nino (Nino3.4=1 degrees C). Following an El Nino, a strengthening of the westward-flowing Equatorial Intermediate Current of about 2.7 x 10(6) m(3) s(-1) shifts about 97 x 10(12) m(3) of Thermostad water from the east to the west, allowing conservation of volume within the Thermostad as the pycnocline above deepens in the east and shoals in the west. This transport and volume change imply a 14 month time scale, consistent with El Nino.

Following strong westerly wind bursts in boreal winter and spring of 2014, both the scientific community and the popular press were abuzz with the possibility of a major El Nino developing. However, during the boreal summer of 2014, the Bjerknes feed...

The failed influence of the 2015-2016 El Nino on California rainfall has renewed interest in the relationship between El Nino and U.S. rainfall variability. Here we perform statistical data analyses and simple model experiments to show that sufficien...